An object falls from a height of $$10 \mathrm{~m}$$ above the ground. After striking the ground it loses $$50 \%$$ of its kinetic energy. The height upto which the object can rebounce from the ground is:
In the circuit shown below, the inductance $$L$$ is connected to an ac source. The current flowing in the circuit is $$I=I_0 \sin \omega t$$. The voltage drop $$\left(V_L\right)$$ across $$L$$ is
A $$12 \mathrm{~pF}$$ capacitor is connected to a $$50 \mathrm{~V}$$ battery, the electrostatic energy stored in the capacitor in $$\mathrm{nJ}$$ is
A uniform wire of diameter $$d$$ carries a current of $$100 \mathrm{~mA}$$ when the mean drift velocity of electrons in the wire is $$v$$. For a wire of diameter $$\frac{d}{2}$$ of the same material to carry a current of $$200 \mathrm{~mA}$$, the mean drift velocity of electrons in the wire is